/*
 * Copyright (c) 2015-2020, www.dibo.ltd (service@dibo.ltd).
 * <p>
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not
 * use this file except in compliance with the License. You may obtain a copy of
 * the License at
 * <p>
 * https://www.apache.org/licenses/LICENSE-2.0
 * <p>
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 * License for the specific language governing permissions and limitations under
 * the License.
 */
package com.icesoft.framework.core.binding.binder;

import com.icesoft.framework.core.binding.annotation.BindEntity;
import com.icesoft.framework.core.binding.binder.remote.RemoteBindingManager;
import com.icesoft.framework.core.binding.helper.ResultAssembler;
import com.icesoft.framework.core.binding.helper.WrapperHelper;
import com.icesoft.framework.core.config.Cons;
import com.icesoft.framework.core.exception.InvalidUsageException;
import com.icesoft.framework.core.util.BeanUtils;
import com.icesoft.framework.core.util.ISetter;
import com.icesoft.framework.core.util.V;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.util.Collection;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.stream.Collectors;

/**
 * Entity实体绑定Binder，用于绑定当前一个entity到目标对象的属性
 */
public class EntityBinder<T> extends BaseBinder<T> {
	private static final Logger log = LoggerFactory.getLogger(EntityBinder.class);

	/***
	 * 给待绑定list中VO对象赋值的setter属性名
	 */
	protected String annoObjectField;
	/***
	 * 给待绑定list中VO对象赋值的setter属性class类型
	 */
	protected Class<?> annoObjectFieldClass;

	/***
	 * 构造方法
	 * @param entityClass
	 * @param voList
	 */
	public EntityBinder(Class<T> entityClass, List voList) {
		super(entityClass, voList);
	}

	/***
	 * 构造方法
	 * @param annotation
	 * @param voList
	 */
	public EntityBinder(BindEntity annotation, List voList) {
		super(annotation.entity(), voList);
	}

	/***
	 * 指定VO绑定属性赋值的setter方法
	 * @param voSetter VO中调用赋值的setter方法
	 * @param <T1> VO类型
	 * @param <R> set方法参数类型
	 * @return
	 */
	public <T1, R> BaseBinder<T> set(ISetter<T1, R> voSetter, Class annoObjectFieldClass) {
		return set(BeanUtils.convertToFieldName(voSetter), annoObjectFieldClass);
	}

	/***
	 * 指定VO绑定属性赋值的set属性
	 * @param annoObjectField VO中调用赋值的setter属性
	 * @return
	 */
	public BaseBinder<T> set(String annoObjectField, Class annoObjectFieldClass) {
		this.annoObjectField = toAnnoObjField(annoObjectField);
		this.annoObjectFieldClass = annoObjectFieldClass;
		return this;
	}

	@Override
	public void bind() {
		if (V.isEmpty(annoObjectList)) {
			return;
		}
		if (V.isEmpty(refObjJoinCols)) {
			throw new InvalidUsageException("调用错误：无法从condition中解析出字段关联.");
		}
		// 直接关联Entity
		if (middleTable == null) {
			this.simplifySelectColumns();
			// @BindEntity(entity = Department.class, condition="this.department_id=id AND this.type=type")
			// Department department;
			super.buildQueryWrapperJoinOn();
			// 查询条件为空时不进行查询
			if (queryWrapper.isEmptyOfNormal()) {
				return;
			}
			List<T> entityList = null;
			// 查询entity列表: List<T>
			if (V.isEmpty(this.module)) {
				// 本地查询获取匹配结果的entityList
				entityList = getEntityList(queryWrapper);
			} else {
				// 远程调用获取
				entityList = RemoteBindingManager.fetchEntityList(module, remoteBindDTO, referencedEntityClass);
			}
			if (V.notEmpty(entityList)) {
				Map<String, Object> valueEntityMap = this.buildMatchKey2EntityMap(entityList);
				ResultAssembler.bindPropValue(annoObjectField, super.getMatchedAnnoObjectList(), getAnnoObjJoinFlds(), valueEntityMap, null);
			}
		}
		// 通过中间表关联Entity
		else {
			if (refObjJoinCols.size() > 1) {
				throw new InvalidUsageException(NOT_SUPPORT_MSG);
			}
			// 提取注解条件中指定的对应的列表
			Map<String, List> trunkObjCol2ValuesMap = super.buildTrunkObjCol2ValuesMap();
			Map<String, Object> middleTableResultMap = middleTable.executeOneToOneQuery(trunkObjCol2ValuesMap);
			if (V.isEmpty(middleTableResultMap)) {
				return;
			}
			// 结果转换Map
			Map<String, Object> valueEntityMap = new HashMap<>();
			this.simplifySelectColumns();
			// 提取entity主键值集合
			Collection refObjValues = middleTableResultMap.values().stream().distinct().collect(Collectors.toList());
			// 构建查询条件
			String refObjJoinOnCol = refObjJoinCols.get(0);
			// 查询entity列表
			List<T> entityList = null;
			// 查询entity列表: List<T>
			if (V.isEmpty(this.module)) {
				queryWrapper.in(refObjJoinOnCol, refObjValues);
				// 本地查询获取匹配结果的entityList
				entityList = getEntityList(queryWrapper);
			} else {
				// 远程调用获取
				remoteBindDTO.setRefJoinCol(refObjJoinOnCol).setInConditionValues(refObjValues);
				entityList = RemoteBindingManager.fetchEntityList(module, remoteBindDTO, referencedEntityClass);
			}
			if (V.isEmpty(entityList)) {
				return;
			}
			String refObjJoinOnField = toRefObjField(refObjJoinOnCol);
			// 转换entity列表为Map<ID, Entity>
			Map<String, T> listMap = BeanUtils.convertToStringKeyObjectMap(entityList, refObjJoinOnField);
			if (V.notEmpty(listMap)) {
				//List<String> joinOnValues = new ArrayList<>(refObjJoinFlds.size());
				for (Map.Entry<String, Object> entry : middleTableResultMap.entrySet()) {
					Object fetchValueId = entry.getValue();
					if (fetchValueId == null) {
						continue;
					}
					String key = entry.getKey();
					T entity = listMap.get(String.valueOf(fetchValueId));
					valueEntityMap.put(key, cloneOrConvertBean(entity));
				}
			}
			// 绑定结果
			ResultAssembler.bindEntityPropValue(annoObjectField, super.getMatchedAnnoObjectList(), middleTable.getTrunkObjColMapping(), valueEntityMap, getAnnoObjColumnToFieldMap());
		}
	}

	/**
	 * 构建匹配key-entity目标的map
	 *
	 * @param list
	 * @return
	 */
	private Map<String, Object> buildMatchKey2EntityMap(List<T> list) {
		Map<String, Object> key2TargetMap = new HashMap<>(list.size());
		StringBuilder sb = new StringBuilder();
		for (T entity : list) {
			sb.setLength(0);
			for (int i = 0; i < refObjJoinCols.size(); i++) {
				String refObjJoinOnCol = refObjJoinCols.get(i);
				String pkValue = BeanUtils.getStringProperty(entity, toRefObjField(refObjJoinOnCol));
				if (i > 0) {
					sb.append(Cons.SEPARATOR_COMMA);
				}
				sb.append(pkValue);
			}
			// 查找匹配Key
			String matchKey = sb.toString();
			Object target = entity;
			if (!(target instanceof Map)) {
				target = cloneOrConvertBean(entity);
			}
			key2TargetMap.put(matchKey, target);
		}
		sb.setLength(0);
		return key2TargetMap;
	}

	/**
	 * 克隆Entity/VO对象（如果与Entity类型不一致，如VO则先转型）
	 *
	 * @param value
	 */
	protected Object cloneOrConvertBean(T value) {
		if (value == null) {
			return value;
		}
		if (value.getClass().getName().equals(annoObjectFieldClass.getName())) {
			return BeanUtils.cloneBean(value);
		} else {
			return BeanUtils.convert(value, annoObjectFieldClass);
		}
	}

	/**
	 * 简化select列，仅select必需列
	 */
	@Override
	protected void simplifySelectColumns() {
		if (!referencedEntityClass.getName().equals(annoObjectFieldClass.getName())) {
			WrapperHelper.optimizeSelect(queryWrapper, referencedEntityClass, annoObjectFieldClass);
		}
	}

}
